bootloader: Use distinct USB PIDs depending on location in flash.

[gps-watch.git] / src / bootloader / main.rs

diff --git a/src/bootloader/main.rs b/src/bootloader/main.rs
index d81da1532baa5b0b41f3a05f5f1adc7e1cf3d084..ca459fdc2eccf1c406b52b6423e8d40aab307be9 100644 (file)
--- a/src/bootloader/main.rs
+++ b/src/bootloader/main.rs
@@ -30,18 +30,37 @@ extern crate common;
 mod flash;
 mod bootloader;
 
+use common::register;
 use common::clock;
 use common::systick;
 use common::port;
 use common::gpio;
 use common::usb_serial;
 
+type Reg32 = register::Register<u32>;
+
 extern {
     fn jump_to_application(address: u32);
 }
 
+#[cfg(bootloader_type = "intermediate")]
 const APPLICATION_ADDR: u32 = 0x0;
 
+#[cfg(bootloader_type = "final")]
+const APPLICATION_ADDR: u32 = 0x8000;
+
+#[cfg(bootloader_type = "intermediate")]
+const USB_PID: u16 = 0x635b;
+
+#[cfg(bootloader_type = "final")]
+const USB_PID: u16 = 0x635c;
+
+unsafe fn application_missing() -> bool {
+    let first_app_word = Reg32::new(APPLICATION_ADDR);
+
+    first_app_word.read() == 0xffffffff
+}
+
 fn bootloader_requested() -> bool {
     let start_ticks = systick::now();
 
@@ -58,19 +77,22 @@ fn bootloader_requested() -> bool {
 pub unsafe extern fn main() {
     clock::configure();
     systick::init();
+    port::init();
 
     // Configure lower left push button.
     gpio::set_direction(gpio::GPIOE, 1 << 24, gpio::Direction::Input);
     port::set_af(port::PORTE, 24, 1);
     port::set_pull(port::PORTE, 24, port::Pull::Up);
 
-    if bootloader_requested() {
-        usb_serial::init(0xf055, 0x635c);
+    if application_missing() || bootloader_requested() {
+        usb_serial::init(0xf055, USB_PID);
 
         let mut b = bootloader::Bootloader::new();
 
-        while b.run() {
+        while b.run() || application_missing() {
         }
+
+        usb_serial::shutdown();
     }
 
     jump_to_application(APPLICATION_ADDR);